I've never been convinced of the need for a protein only shake. The reason that people put on 20 pounds etc in a few weeks is because a lot of them are filled out with sugars, it is not possible to add that much lean muscle in that amount of time. A healthy diet will give you most of the protein you need for a regular workout.
The only people who really need vast amounts of protein are those who take steroids as they increase protein synthesis. Taking roids though is NOT a good idea, especially if you are young and new to training.
I have always prefered a general supplement like Reflex - One Stop. Its good value and contains a good mix of protein,carbs vitamins etc...
From time to time I'll take dessicated liver as well.
Steer clear of Maximuscle as it is over priced.
If you are taking Creatine, understand what it does. It helps with muscle contraction and repair. It also draws water into the muscle cells and gives you a more "pumped" appearance. This should increase your strength and endurance. It is not in itself a "muscle builder".
It definately works as whenever I have used it it does increase my re ps count and max lift.
Follow the instructions though and follow the loading regime for the first week. Take it for a couple of months and then have a break. They are still not sure of continuous long term usage..
Don't believe the "instant" creatine serums as they don't work..
One last thing, if you're up for it, try some Nitic Oxide, its a blood booster that gives you a huge pump. Excellent for getting a vascular look, and as its one of the main ingredients of Viagra, it has some quite handy side effects